As the disintegrative factor is on a per preset, per generator basis, there are two ways you can deal with this requirement.
1. Run the MW with disintegrative turned on, on one generator and the regular MW frequencies on another generator.
2. Build two presets, one with it turned on, and one with it turned off. Then combine them into a preset chain. This will allow you to run them all on one generator, but is a bit more work.
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